Device for receiving and separating chips created by machine-tools and coolant (drive)

ABSTRACT

The invention relates to a device for receiving and separating chips and cooling liquid collecting on machine tools, in which a transport element is guided along a filter drum at a radial distance from the latter on guide rails, and cooperating driver elements acting only in the circumferential direction on the filter drum and arranged in each case at a distance from one another are provided on the transport element and on the filter drum.

The invention relates to a device for receiving and separating chips andcooling liquid collecting on machine tools, the cooling liquid beingreturned for reuse and the chips being discharged, having a receivingtank for receiving the chips and the cooling liquid, a rising guidesection adjoining the receiving tank, an elevated delivery sectionadjoining the guide section, a chain-like closed transport elementwhich, at least in the region receiving the chips and the cooling liquidand in the delivery section, is guided via deflecting elements, of whichat least one is coupled to a rotary drive, and a rotatably mountedfilter drum which is in drive connection with the transport element.

In a known device of this type (U.S. Pat. No. 6,332,893), a transportelement is directed partly around the filter drum and directly causesthis drum to rotate in the process. It follows from this that thebearings of the drum are radially loaded by the transport element, thatis to say that the wear on these bearings increases. Furthermore, as aresult of the direct drive connection between transport element andfilter drum, the circumferential speed of the filter drum must alwayscorrespond to the speed of the transport element.

The object of the present invention, then, is to reduce the bearing loadof the filter drum in a device of the type mentioned at the beginningand to make it possible for a filter cake to form on the outside on thecircumference of the drum despite a continuously revolving transportelement, this filter cake positively influencing the filter effect.

This object is achieved according to the invention in that the transportelement is guided along the filter drum at a radial distance from thelatter on guide rails, and in that cooperating driver elements actingonly in the circumferential direction on the filter drum and arranged ineach case at a distance from one another are provided on the transportelement and on the filter drum.

In this case, the pressure exerted during the deflection of thetransport element in the region of the filter drum is absorbed by theguide rails and the bearings of this drum are relieved. At the sametime, the filter drum does not automatically follow the movement of thetransport element.

On the contrary, the arrangement of the cooperating driver elements onthe filter drum on the one hand and on the transport element on theother hand determines the phases in which a rotation takes place and, onthe other hand, in which the filter drum is stopped. During these stopperiods, a filter cake can form in a perfectly desirable manner on thelateral surface of the filter drum, this filter cake increasing thefilter effect. In a manner known per se, this filter cake can bedissolved from the inside of the filter drum by jets of filtered coolingliquid in order not to allow the thickness of the filter cake formed toincrease too much.

The driver elements on the filter drum are expediently designed asprojecting pins and the driver elements on the transport element areexpediently designed as projecting stops cooperating with the pins.

Furthermore, provision is made according to the invention for the driverelements to have a crank mechanism, the crank of which is in driveconnection 35 with the transport element and the rod of which carries adriver element which engages in the tooth system of a ratchet wheelcoupled to the filter drum. In this case, the crank radius of the crankmechanism can be adjustable. As a result, the angle by which the filterdrum is advanced during a revolution of the crank can be determined.

Both drive variants can in each case be attached on one side or on bothsides of the filter drum. On the one hand, the circumferential speed canbe increased by the drives alternately driving the drum on both sides;on the other hand, torsional forces are avoided during synchronous driveof both drum sides.

Furthermore, the device according to the invention may be designed insuch a way that the transport element is a scraper chain guided at itstwo sides in the housing of the device and having scraper webs runningtransversely to the transport direction and projecting downwards in theregion of the bottom strand.

Furthermore, the invention provides for the transport element to be ahinged belt conveyor guided at its two sides in the housing of thedevice and having supporting sections running transversely to thetransport direction.

A few embodiments of the device according to the invention are describedbelow with reference to drawings, in which:

FIG. 1 shows a side view of a device according to the invention having ascraper chain,

FIG. 2 shows a side view of a device according to the invention having ahinged belt conveyor,

FIG. 3 shows a detail view of a filter drum in combination with ascraper chain,

FIG. 4 shows a detail view of a filter drum in combination with a hingedbelt conveyor,

FIG. 5 shows an axial section through a filter drum designed accordingto the invention for drum drives according to FIGS. 3 and 4,

FIG. 6 shows a detail view of a further embodiment with crank drive ofthe filter drum in combination with a scraper chain,

FIG. 7 shows a detail view of a further embodiment with crank drive ofthe filter drum in combination with a hinged belt conveyor,

FIG. 8 shows an axial section through a filter drum designed accordingto the invention with a drum drive in accordance with the embodimentsaccording to FIG. 6 or 7.

FIG. 1 shows the side view of an embodiment of the device according tothe invention having a receiving tank 1 which is open at the top andwhich receives chips and cooling liquid collecting on machine tools.This receiving tank has an overflow edge 2. Adjoining the receiving tankis a rising guide section 3, which merges into an elevated deliverysection 4.

Here, a scraper chain roller-guided on both sides is provided astransport element. This scraper chain is guided around a bottomdeflecting element 6 at the end of the receiving tank 1 and runs in theregion of the delivery section 4 around a top deflecting element 7,which is coupled to a drive (not shown). It carries scraper elementswhich are arranged at a distance apart and which project downwards inthe region of the bottom strand, that is to say in the direction of thebottom of the receiving tank 1, or towards the side wall 10 of therising section 3. The transport direction of the scraper chain 1 isindicated by the arrow 11.

A filter drum 12 which is rotatably mounted in the housing of the deviceis provided. The scraper chain runs around the filter drum at a radialdistance which is determined by a guide rail 13. Driver elements areprovided on the scraper chain 5 and on the filter drum 12, these driverelements gradually advancing the filter drum 12 intermittently duringoperation of the device.

The embodiment according to FIG. 2 differs from that according to FIG. 1merely in the fact that the transport element used is a hinged belt 14instead of a scraper belt, this hinged belt 14, in contrast to a scraperbelt, receiving and carrying the material to be transported on its topside. In this case, the hinged belt 14 is covered on the underside ofits top strand with a baffle 8.

FIG. 3 shows pins 20 which are arranged equidistantly on the filter drum12 and cooperate with stops 21 which 15 are fastened to the scraperchain 5.

Furthermore, the web-shaped scraper elements 9 and the stops 21 may forma constructional unit.

FIG. 4 shows an embodiment according to FIG. 3 with a hinged belt 14.

FIG. 5 shows a section through a filter drum 12 having a hinged belt 14,the lateral rollers 22 of which run in guides 23. Furthermore, of thehinged belt 14, a retaining rod 24 is shown, on which a web-like scraperelement 9 projecting downwards sits. The filter drum 12 is of identicaldesign towards its two ends and is rotatably mounted in the housing ofthe device. It is open on both sides and therefore forms on both sidesan outlet for the cleaned cooling liquid passed through the filter wall25.

The embodiment according to FIG. 6 differs from that 35 described withreference to FIGS. 3 and 4 in that the driver elements are formed by acrank mechanism 26. This mechanism has a gearwheel 27 which is rotatableabout a fixed axis (not shown). In this case, the gearwheel engagesbetween the rollers of the scraper chain 5, which interacts at the rearwith a support 28, so that the scraper chain 5 cannot give way to theaction of the gearwheel 27.

A crank pin 29 sits on the gearwheel 27 eccentrically to the axis of thegearwheel and carries a push rod 30, and sitting in turn on the end ofthe latter is a driver element 31, which engages in the tooth system ofa ratchet wheel 32.

During operation of the scraper chain 5, the rotation of the gearwheel27, via the crank pin 29, successively causes the ratchet wheel 32 toadvance by at least one tooth in each case during each complete rotationof the gearwheel 27.

By radial displaceability of the crank pin 29 in the gearwheel 27, thestroke of the toothed rack [sic] 30 can be varied, so that the ratchetwheel 32 can be moved by more than one tooth during a rotation of thegearwheel 27.

A particular advantage of this embodiment can be seen in the fact that,here, all the elements for the gradual advance of the filter drum areaccommodated in a region of the device in which contamination can beexpected only to a relatively small extent.

FIG. 7 shows the embodiment according to FIG. 6 with the exception thatthe transport element here is a hinged belt conveyor.

FIG. 8 shows a section through the filter drum and contiguously throughthe crank mechanism in accordance with the device shown in FIG. 7.

LIST OF DESIGNATIONS

-   1 Receiving tank-   2 Overflow edge-   3 Guide section-   4 Delivery section Scraper chain-   6 Deflecting element-   7 Deflecting element-   8 Baffle-   9 Scraper elements Side wall-   11 Arrow-   12 Filter drum-   13 Guide rail-   14 Hinged belt-   15-   16-   17-   18-   19 Pin-   21 Stops-   22 Rollers-   23 Guides-   24 Retaining rod Filter wall-   26 Crank mechanism-   27 Gearwheel-   28 Support-   29 Crank pin Push rod-   31 Driver element-   32 Ratchet wheel

1. A device for receiving and separating chips and cooling liquidcollecting on machine tools, the cooling liquid being returned for reuseand the chips being discharged, comprising: a receiving tank forreceiving the chips and the cooling liquid, a rising guide sectionadjoining the receiving tank; an elevated delivery section adjoining theguide section; and a chain-like closed transport element which, at leastin the region receiving the chips and the cooling liquid and in thedelivery section, is guided via at least first and second deflectingelements, wherein: at least one of the first and second deflectingelements is coupled to a rotary drive, and a rotatably mounted filterdrum which is in drive connection with the transport element; thetransport element is guided along the filter drum at a radial distancefrom the latter on guide rails, the guide rails are located between thefilter drum and the transport element to define said radial distance;and cooperating driver elements acting only in the circumferentialdirection on the filter drum and arranged in each case at a distancefrom one another are provided on the transport element and on the filterdrum.
 2. The device according to claim 1, wherein the driver elements onthe filter drum comprise projecting pins and the driver elements on thetransport element comprise projecting stops cooperating with the pins.3. The device according to claim 1, wherein the driver elements comprisea crank mechanism having a crank and a rod, wherein the crank is indrive connection with the transport element and the rod carries a driverelement which engages in the tooth system of a ratchet wheel coupled tothe filter drum.
 4. The device according to claim 3, wherein the crankof the crank mechanism comprises a gearwheel and engages on rollers ofthe transport element.
 5. The device according to claim 3 or 4, whereinthe crank radius of the crank mechanism is adjustable.
 6. The deviceaccording to claim 5 wherein the transport element comprises a scraperchain guided on two sides in the housing of the device and havingscraper webs running transversely to the transport direction andprojecting downwards in the region of the bottom strand.
 7. The deviceaccording to claim 6 wherein the driver elements connected on the onehand to the transport element and on the other hand to the filter drumare provided on both sides of the transport element.
 8. The deviceaccording to claim 5 wherein the transport element comprises a hingedbelt conveyor guided on two sides in the housing of the device andhaving supporting sections running transversely to the transportdirection.
 9. The device according to claim 8 wherein the driverelements connected on the one hand to the transport element and on theother hand to the filter drum are provided on both sides of thetransport element.
 10. The device according to claim 5 wherein thedriver elements connected on the one hand to the transport element andon the other hand to the filter drum are provided on both sides of thetransport element.
 11. The device according to one of claims 1, 2, 3, or4, wherein the transport element comprises a scraper chain guided on twosides in the housing of the device and having scraper webs runningtransversely to the transport direction and projecting downwards in theregion of the bottom strand.
 12. The device according to claim 11wherein the driver elements connected on the one hand to the transportelement and on the other hand to the filter drum are provided on bothsides of the transport element.
 13. The device according to one ofclaims 1, 2, 3, or 4, wherein the transport element comprises a hingedbelt conveyor guided on two sides in the housing of the device andhaving supporting sections running transversely to the transportdirection.
 14. The device according to claim 13 wherein the driverelements connected on the one hand to the transport element and on theother hand to the filter drum are provided on both sides of thetransport element.
 15. The device according to one of claims 1, 2, 3, or4, wherein the driver elements connected on the one hand to thetransport element and on the other hand to the filter drum are providedon both sides of the transport element.